Quotes of justice, education, religion and race said by Martin Luther King Jr.

On Monday, the US celebrates the life and legacy of civil rights activist Martin Luther King Jr, who would have turned 89 years old.

The Baptist minister, Nobel Laureate and civil rights activist dedicated his life to "work for peace, social justice, and opportunity for all Americans".

Beginning in 1971, three years after he was assassinated in Memphis, Tennessee, many US cities and states began to mark what is now known as "MLK Day".

In 1983, then-President Ronald Reagan signed a bill that created a federal holiday in King's honour. It was first observed three years later and continues to be celebrated on the third Monday of January. The day was chosen because it is often around King's birthday, January 15.

More than 30 years later, the day is still traditionally celebrated as one of service, honouring King's legacy and words, including his famous "I have a dream" speech, which continue to resonate today.

Here is a list of some of King's most emblematic quotes:

1. On injustice

"Injustice anywhere is a threat to justice everywhere," King wrote from the Birmingham city jail in 1963.

"We are caught in an inescapable network of mutuality, tied in a single garment of destiny. Whatever affects one directly, affects all indirectly," he said.

"Never again can we afford to live with the narrow, provincial, 'outside agitator' idea. Anyone who lives inside the United States can never be considered an outsider anywhere within its bounds."

Martin Luther King Jr:Injustice anywhere is a threat to justice everywhere.

2. On truth and love

"I refuse to accept the cynical notion that nation after nation must spiral down a militaristic stairway into the hell of thermonuclear destruction, " King said in his acceptance speech of the Nobel Peace Prize in 1964.

"I believe that unarmed truth and unconditional love will have the final word in reality," he continued.

"This is why right temporarily defeated is stronger than evil triumphant. I believe that even amid today's mortar bursts and whining bullets, there is still hope for a brighter tomorrow."

King received the Nobel Peace Prize for his non-violent fight against racial inequality.

Martin Luther King Jr:I believe that unarmed truth and unconditional love will have the final word in reality.

3. On education

"To save man from the morass of propaganda, in my opinion, is one of the chief aims of education. Education must enable one to sift and weigh evidence, to discern the true from the false, the real from the unreal, and the facts from the fiction," King wrote in the Morehouse College Student Paper, The Maroon, in 1947.

"Intelligence plus character - that is the goal of true education," he said.

"If we are not careful, our colleges will produce a group of close-minded, unscientific, illogical propagandists, consumed with immoral acts. Be careful, brethren! Be careful, teachers!"

Martin Luther King Jr:Intelligence plus character - that is the goal of true education.

4. On racism and violence

"The non-violent Negro is seeking to create the beloved community. He directs his attack on the forces of evil rather than on individuals," King said in a speech delivered in Finney Chapel in 1957, as reported by the Chronicle in 2008.

"The tensions are not between the races, but between the forces of justice and injustice; between the forces of light and darkness."

Martin Luther King Jr:The tensions are not between the races, but between the forces of justice and injustice.

5. On religion

King was the author of the book Strength To Love, a collection of sermons that he wrote on a number of topics, including religion.

In one of King's sermons, he extolled the need for a "tough mind.

"The modern world", he said, has far too much "softmindedness" of "unbelievable gullibility".

King also had great appreciation and respect for science.

"There may be a conflict between softminded religionists and toughminded scientists. But not between science and religion," he said.

"Their respective worlds are different and their methods are dissimilar.

"Science investigates; religion interprets. Science gives man knowledge which is power; religion gives man wisdom which is control. Science deals mainly with facts; religion deals mainly with values. The two are not rivals. They are complementary."

"True peace is not merely the absence of tension: it is the presence of justice," Martin Luther King responded after being accused of disturbing the peace during the "bus boycott" in Montgomery, Alabama.

The bus boycott was a 13-month political and social protest against the policy of racial segregation on public transit.

It ended on December 20, 1956. The US Supreme Court ultimately ruled that segregation on public buses is unconstitutional.

Martin Luther King Jr:True peace is not merely the absence of tension: it is the presence of justice.